[71Formula]

I have thrown a rod bearing in my 71 Firebird 400 and now I'm debating on what to do. I've found a low miles 2002 Chevy 5.3 Liter Fuel injected motor with a 700R4 tranny with computer and wire harness for a very reasonable price (2k). Would this be a very good engine in my 3600 lb Firebird (less weight than that without the Pontiac block in there)? Has anyone done this? If not the 5.3, how about the 6.0L or 8.1L? I'm just considering this to build a good reliable streetable car with decent gas mileage. My Pontiac 400 is rebuildable and I am not by any means apposed to building it back up. But, the modern EFI with overdrive is for some reason appealing. Any suggestions, comments?